Session VII Pelvis and Acetabulum

Management of the Morel-Lavallé Lesion

David J. Hak, MD, Steven A. Olson, MD, Joel M. Matta, MD

University of California at Davis, Sacramento, CA; Good Samaritan Hospital, Los Angeles, CA

Purpose: To review the diagnosis and treatment of the Morel-Lavallé lesion in acetabular and pelvic trauma.

Conclusions: There is a high incidence of bacterial colonization in closed degloving injuries associated with severe pelvic trauma. The Morel-Lavalle' lesion should be treated by thorough debridement prior to or at the time of the pelvic or acetabular surgery.

Introduction: The Morel-Lavalle' lesion is a closed degloving injury, usually in the region of the greater trochanter, which is seen in association with pelvic and acetabular fractures. A cavity of hematoma and liquefied fat is produced from a shear injury in which the subcutaneous tissue is torn away from the underlying fascia. The significance of the soft tissue injury may not be initially apparent, and may be overlooked as attention is focused on their bony injuries.

Materials and Methods: We reviewed the records of 24 patients who sustained a Morel-Lavalle' lesion. Physical findings included a loss of local sensation and a soft fluctuant area over the lesion. Mechanism of injury was a motor vehicle accident (MVA) in 13 cases, a pedestrian vs. MVA in 5 cases, an industrial crushing injury in 4 cases, and one case each of a train vs. MVA and train vs. pedestrian. Six patients sustained a Tile C lateral compression injury with sacral and pubic ramus fractures, six patients had sacroiliac disruptions, six patients had sacroiliac joint disruptions associated with acetabular fractures, five patients had an acetabular fracture alone, and one patient had no associated pelvic fractures. Sixteen patients were women and 8 were men. The average age of the patients was 35 years (range 17 to 77 years) and the average follow-up was 32 months (range 1 month to 9 years).

Results: Cultures from the Morel-Lavalle' lesion were positive in 46 per cent (11 of 24) of the cases. The organism cultured was coagulase negative Staphylococcus in 4 cases, Staph. epidermidis in 3 cases, Pseudomonas in 3 cases, Moraxella in 1 case and a Bacillus species in 1 case. All patients underwent debridement through a lateral incision on the proximal thigh. All necrotic fat and hematoma was debrided. The incision used for the debridement was left open and treated with wet to dry dressings. In the majority of cases this wound was allowed to heal by secondary intention. Four patients underwent delayed primary closure and two underwent split thickness skin grafting. One patient whose degloving injury was initially drained at an outside hospital without aggressive debridement developed a chronic soft tissue infection. Three patients subsequently developed deep bone infections, only one of which had a positive culture at the initial debridement. No patient who underwent delayed primary closure developed an infection. One patient developed an infection in the sacroiliac joint, one patient developed an infection of the ilium, and one immunocompromised patient underwent a Girdlestone procedure for hip infection three years after fixation of his acetabular fracture.